Totalizer



May 6, 1958 E, J. GROTH, JR 2,833,469

TOTALIZER lFiled April 25. 1955 2 sheets-sheet 1 INVENT OR Ezra/rd irai@ B'Y M May 6, 1958 v. GRO-TH, JR

TOTALIZER 2 Sheets-Sheet 2 Filed April 25, 1955 rorAuzER Edward John Groth, Jr., Overland, Mo., assigner to Universal Match Corporation, Ferguson, Met, a corporation of Delaware Application April 25, 1955, Serial No. 503,414 18 Claims. (Cl. 23S-mal) rThis application relates to a totalizer and more particularly to a `device for totalizing respiration.

In totalizing respiration of an animal it is necessary to ascertain the sum of the air respired within a predetermined period, for example, live minutes. In one prior art Ischeme for totalizing respiration a curve of the volume of air breathed in and out versus time is obtained from a recorder, and the peak positive and negative values of the respiration curve are totaled by actually measuring each of the peak ordinates on the curve and `summing these ordinates without regard to algebraic sign, This process is quite tedious and time-consuming. The apparatus of the present invention totalizes respiration automatically. While the invention has its primary application in this held, it may be employed more generally in totalizing the successive ordinates of a curve, particularly where it isdesired to add the successive peak ordinates of a quasi-sinusoidal signal curve without regard to algebraic sign.

Accordingly, it is a primary object of the invention to provide an improved totalizer. l

Another object of the invention is to provide a unique device for totalizing the successive maximum and minimum ordinates of a signal.

A further objectof the invention is to provide a system for summing the successive maximum and` minimum ordinates of a quasi-sinusoidal signal without regard to algebraic sign.

An additional object of the invention is to provide unique respiration totalizer.

Yet another object of the invention is to provide a measuring system wherein a signal is stored in a first storage means for a predetermined period and then transferred to a second storage means, which also receives the signal stored in the first means during successive periods.`

Briefly, the invention comprises a cyclic storage means which stores an electrical charge proportional to the successive peak ordinates of an input signal, an integrating means for storing the charge transferred from the cyclic storage means periodically, a switching means for controlling the transfer from the cyclic storage means to the integrating means, a comparison means for comparing the input signal with a reference level for determining the correct instants to operate the switching means', and anindicator means for registering the total of the signal stored in the integrating means.

The foregoing and other objects of the invention will become more readily apparent in the following detailed description or' the invention when taken in conjunction with the acompanying drawings, wherein:

Figure l is a block diagram of a preferred form of the invention;

Figure 2 is a graph of a typical curve which represents a signal to be totalized; and l Figure 3 is a circuit diagram of a preferred form of the invention.

Referring to Figure l, the signal at the input of the system, which may represent the instantaneous values of `minals are connected to a start and stop ZddAQ Paz'tenteci 'May 6, 1958 'icc the `volume of air breathed by an animal, is passed through an ampliter 10 which, by virtue of its variable feedback characteristics, serves as a variable cut-olii low pass iilter.` The purpose of this ampliiier is `to iilter the incoming signal to remove extraneous noise and small variations in the signal which are really not related to the breathing process. e. g., the heart beat. The signal is then applied to a cyclic storage circuit l2, which, as will appear more fully below, may comprise a pair of condensers charged through a pair of diodes in accordance with the `peak positive and negative ordinates, respectively, of the input signal during onetcycle. These two charges represent the maximum and minimum diierential volumes `encountered during that breathing cycle. Figure 2 illustrates a typical input signal having a series of successive peak ordinates P1 through P7 varying about a base line B. The positive ordinates would then be stored in one of the capacitors and the negative ordinates in the other.

At the end of a cycle, the charge stored in the two capacitors is transferred by means or" a switching arrangement 14 to a large capacitor which may be in the feedback path of an integrating amplier i6. The switching circuit is operated from a comparison circuit lil, which compares the level of the input signal from amplier it) with a reference level, which, in the example illustrated, is a lioating ground level represented by base line B. As will become more apparent below, the switching circuit is operated to discharge the cyclic storage circuitat the end of each cycle. ln this mannerpthe two capacitors in the cyclic storage circuit are completely discharged and are made available for data pertaining to the subsequent breathing cycle. The charges which they had accumulated are stored in the large capacitor in the integrating ampliiier t6 and the total amount of charge stored by the integrating device is registered on an indicator 2d. in order that the charges stored in circuit 12 will be totaled wtihout regard to sign, they must be applied to the integrating amplifier additively. This is accomplished, as will appear hereinafter, `by the construction of the switching circuit. A cycle counter l5 may also be operated by the switching circuit so as to record the total number of breathing cycles in counter may be of `the conventional multi-wheel solenoid operated type.

Referring now to Figure 3, the input signal may be applied to the system at a pair of input terminals 22 and may `tbe obtained from the recorder previously mentioned or from a `strain gauge amplifier connected to a strain gauge which is attached to the subject. The input terswitch 2d having a pair of ganged switch arms 25, 2S. Switch arm 25 is arranged to open and close a circuit with Contact 3h), while switch arm 28 isarranged to open and close circuits alternately with contacts 32` and 34. Switch arm 28 is connected through conductor 35 toa sensitivity control Tt at the input of the variable cut-oit frequency amplier. The sensitivity control may be a conventional rheostat with a variable tap.

Electric power for the system is provided by a pair of conventional power supplies (not shown) which supply plus and minus potentials with respect to a iloating ground level. In the form illustrated, the power supplies provide positive 300 volts on conductor 40, negative 300 volts on conductor ft2, and positive l5() volts on conductor 4.4i, all with respect to the potential on a lioating ground line 46. This line is preferably connected to the chassis of the apparatus through one or more condensers, such as condenser 4h. The two 300 volt supplies should be very closely regulated, but the regulators may be quite conventional. The negative regulator may employ conventional gas regulator tubes and the positive regulator the test period, This 3 may utilize the negative supply as its standard. ln this manner, variations ot the negative supply will be reliected as similar variations in the positive supply. Of course, if the loop gain of the regulators is quite high, these variations will be quite small. y v

In the form illustrated the variable cut-oli frequency amplifier comprises tubes 5h, 52, and 56. Tubes 5@ and 56 may be dual triodes, for example, and tube 54 a gas regulator tube. The ampliiier is of the feedback type and in the form shown as an output to input ratio of three. This ratio is determined resistorsb and 60, which have a ratio of one to three. Resistor 53 is connected to the variable tap of sensitivity control 38, while resistor 6) is connect-ed to conductor 62, which provides a feedback path from the output to the input of the amplifier.

The cut-ofi frequency of the amplifier is varied by altering the internal loop gain, and by the use of proper internal phase shaping networks. These networks are constituted by resistors 6d, 66, 63, 7d, 77E., conjunction with capacitors "i6, 7d, and til?. The variation of the internal loop gain is accomplished by adjustment of the variable tap switch h2 in conjunction with the series string of resistors 8d connected in the input circuit of the amplifier. y

The ampliiier must operate in the extremely low frequency region of one or two cycles per second, and thus a D. C. path is provided from its input to its output. The signal at the variable tap of switch S2 as applied to the grid of the first triode section of tube 50 and is i coupled from the plate of the first triode section to the grid of the second triode section. Resistor 63 in the coupling circuit may be variable as indicated so asv to provide a zero adjustment. The plate of the second triode section of tube Sti is coupled to the grid of tube 52, and the signal from the plate of this tube is coupled to the grid of the tirst triode section of tube 56 through a coupling circuit including gas regulator tube 54 and a resistor capacitor network S6, 38. The signal is then coupled from the plate of the hrst triode section of tube 56 to the grid of the second triode section and from the plate of the latter section back to the input circuit through line 62. The cathode of the lirst triode section of tube 56 is also connected to this line, and since the cathode of the second triode section is connected to the minus 300 volt line, the two triode sections of tube S6 are connected in series between the plus 300 and minus 300 volt supplies. Resistors 9d, 92, 94, and 96 are plate load resistors connecting the plates of the respective tubes to the plus 300 volt conductor di); resistors 9S and 1% are cathode load resistors; while resistors 102, Mld, 1%, w8 and llt) form a part of the coupling circuits for the respective tubes. lt will be noted that a voltage divider circuit exists between the plus 300 and minus 300 volt supplies for the plates of tubes Sil, 52, and the iirst section of tube S6.

After the breathing signal has been amplified and smoothed by the input amplifier, it is passed to a double diode charging circuit which charges a pair of capacitors in such a manner that their charges represent the maXimum and minimum values of the breathing signal during one complete breathing cycle. Reference numeral 112 designates the double diode charging tube, the cathode of one section and the plate of the other section being connected together and to conductor 62, which receives the output of the variable cut-oli frequency amplifier, as described previously. Tube 1M is arranged to charge a capacitor lid from the plus G volt line 4t) and a capacitor 31.16 from the minus 3G@ volt line d2. Condenser 11d is connected to the switch arm of a single pole double throw switch da. ln the position shown, switch da connects condenser E14 to the plate of one section of the diode 112, while in its alternate position switch da connects condenser 114 to the input of the and 74 in integrating amplier, as will appear more fully here- 4 inafter. Another condenser 11S is permanently connected between the plus 300 volt line 40 and plate of the irst diode section. This condenser is also connected through a resistor l2@ to the arm of a single pole single throw switch 3u, which, when closed, connects the condenser to the iioating ground line 46.

Condenser 1l6 is associated with a pair of single pole double throw switches 5a and 5b, which are adapted to be operated in unison. With these switches in the positions illustrated, condenser 116 is connected from the cathode the second section of diode 112 to the minus 300 volt line d2. With the switches in their alternate positions, the condenser is connected from the plus 300 volt line 40 through a resistor 122 to the arm of switch Another condenser 124 is connected permanently between the cathode of the second diode section of tube MZ and the minus 300 volt line 4t2.

Tube 126, which may be a dual triode, forms a part of the comparison circuit. This tube is arranged as a dual cathode follower. lts plates are connected directly to the plus 300 volt line titi, and its cathodes are connected through load resistors 128 and i3d) to the minus 300 volt line 42. The control grid of the iirst triode section of tube 26 is connected to line 62, i. e., the output ot"- the variable cutotf frequency ampliiier, and the control grid of the second triode section is connected to the floating ground line 46. A relay coil 1 of a polarized relay is connected directly across the cathodes of tube 126.

The integrating amplifier comprises tubes 132, 13d, 136, and L38. Tubes 132 and 138 may be dual triodes as illustrated and tube 136 a gas regulator tube of the same type as tube 54 in the variable cut-oit' frequency amplifier. The input to the grid of the tirst triode section of tube 132. is obtained through resistor from the switch arm of switch la when the latter is closed on its left contact. The signal at the plate of the iirst triode section of tube 132 is coupled through a resistor network comprising resistors Mii, 142, and 14d to the grid or' the second triode section. Resistor 142 may be variable to provide a Zero adjustment. The plate of the second triode section of tube 132 is coupled through a resistor network comprising resistors M6 and 148 to the grid of tube 134 and the plate of this tube is coupled through a network comprising gas regulator tube 136, resistors and 52, and condensers 15d and 156 to the grid of the irst section of tube 13S. The plate of this section is coupled through a network comprising resistors 15S and 16@ to the grid of the second triode section of tube 13S. The plate of the second triode section is connected through a resistor 162 to one terminal of an indicator 164, which may be a microammeter, the other terminal of which is connected to the floating ground line 46. The plate of the second section of tube 133 is also connected to a feedback circuit including condensers 166, and a conductor 168 connected to the grid of the first section of tube 132. Three condensers 166 have been connected in parallel to obtain the required storage capacity, but it ywill be apparent that one very large condenser or a plurality of smaller ones could be utilized. The feedback condensers are arranged to be discharged through a resistor 1754) by a single pole Single throw switch 172, which when closed, completes the discharge circuit.

The integrating amplifier includes plate load resistors T174, T76, 73, and 18u, and cathode load resistors IGZ, t91. Resistor 19@ and capacitor 192 are included in a phase shaping network, and the same is true of the previously described resistor 152. and condenser 156. These networks determine the phase characteristics or the aniplitier. it will be noted that the integrating amplifier is generally similar to the variable cut-off frequency amplitier in its construction.

The switching circuit of Figure 1 includes the switches noted in the foregoing description, a plurality of additional switches, and a plurality of relay coils. These coils include relay coil 1 described in connection with the comparison tube 126 and relay coils 2, 3, 4, and 5. ln practice, coil 3 is arranged to operate switch 3a described in connection with capacitor 118; coil 4 is arranged to operate switch 4a described in connection with capacitor 114; coil 5 is arranged to operate switches 5a and 5b described in connection with condenser 116; and coil 1 is arranged to operate a Single pole single throw switch 1a the arm of which, it will be noted, is connected through a resistor 194 to the plus 150 volt line 44. Where necessary to clarify the circuit diagram, the switches have been separated from the associated operating coils.

n Relay coil 2 operates a single pole double throw switch 2a, the arm of which is connected to the contact of switch la; relay coil 3 also operates a single pole double throw switch 3b, the arm of which is connected to the floating ground line; and relay coil d also operates a single pole single throw switch 4b, the arm of which is connected to the plus 150 volt line. Relay coil 2 also operates a single pole single throw switch 2b, which, when closed, energizes the cycle counter from the 115 volt, 60 cycle supplyat 15a. One end of relay coils 2, 4, and 5 is connected through conductor ll96 to the floating ground line 46. The other end of relay coils i and e" is` connected to the upper terminal of switch 2c. The other end of relay coil 2 is connected through a resistor 198 to the lower contact of switch 2a, to switch arm 26 of the start-stop switch 24, and through conductor 2d@ to the arm of a single pole single throw switch 2tl2, which is ganged to the previously described arm of switch M2. Switches 172 and 202, as will appear hereinafter, constitute a reset switch 203. n n

The `lower contact associated with switch arm 26 is connected to the plus l5() volt line lid, which may `include a resistor 204. The lower contact Eid associated `with switch arm 28 is connected through conductor Mo to the iloating ground line 46. The contact of switch lb is connected through a resistor 206 to one side of coil 3, the other side of this coil being connected to the upper contact of switch 3b. The lower contact of this switch is connected through conductor-208 to condenser 12d. A condenser 210 may be connected across relay coil 3 to provide a time delay. The `contact of switch lb is also connected through a resistor 212 and resistor lg@ to coil 2. The purposes of the various connections will become more apparent in the following description of the operation of the invention.

After the line power has been applied to the instrument and a warm up time of l0 to l5 minutes allowed, the integrating amplifier should be zeroed by adjusting resistor 142. The meter 164 will thereby be made to read zero. The breathing cycle counter lo' should also be zeroed. While the integrating amplifier is being zeroed, the reset switch 203 should be moved to its closed posi tion. The sensitivity control 38 should be adjusted to its desired value, and the frequency control d2 should be set to a value corresponding to approximately two times the maximum expected breathing rate during the run that is to take place. ln the case of monkeys, for example, with a normal breathing rate of once per second `'and with a maximum expected breathing rate of perhaps two per second, this control would be set to four cycles per second cut-ofi frequency. In the case of humans with a breathing rate of about one-half cycle per second and with a maximum instantaneous expected rate of about one cycle per second, the control should be set for a two cycle per second cut-oit. These settings will ensure that the variable cut-off frequency `amplifier will pass a suiciently wide frequency band with a substantially uniform response. At the beginning of the test run the reset switch will be in the position illustrated as will the `start and stop switch With the switches in this position, the totalizer will count the breathing cycles and totalize the volume until switch 24 is moved to the stop and hold position at the end of the run. The total volurne will be read on meter i164, the sensitivity of which `depends upon the value of resistor 162. lf in a very long test run the meter reaches its full scale before the end of the run, the reset switch may be momentarily closed so as to reset meter 16d to zero and then the run may be continued. To obtain the total Volume for the entire run, the successive readings on the meter must be added at the end of the run. The detailed operation of the volume totalizing circuit will now be described.

Condensers lil@ and ilo are the cyclic storage condenser-s which are periodically discharged to the input of the integrating amplifier, while condensers lid and E24 are provided to prevent the circuit from drifting during the time that condensers littland M6 are discharged. At the beginning of a breathing cycle, t1 in Figure 2, one terminal of each of the condensers will be at the .dealing ground potential. One terminal of condeusers iid and .lid is connected permanently to the plus 300 volt line, one terminal of condenser 12d is connected permanently to the minus 300 Volt line, and at the beginning of the cycle one terminal of condenser 116 is connected to the minus- 300 Volt line. As the cycle proceeds toward t2 into the negative region, the terminals of capacitors 11d and 11S which are connected to diode i12 will be pulled down from the base level B (the floating ground level) in accordance with the decrease in potential on line 62 at the output of the variable cutoii frequency amplifier. Condensers lid and lib will thus be charged to a potential greater than 300 volts by an amount corresponding to the minimum of the breathing cycle, or the peak value P2 in Figure 2, and will main- 'tain` these charges temporarily. When t2 is reached, the plate of the second half of the dual diode liz' will be pulled positively above the base level B and condensers lilo and ft2/l will be charged to a value greater than 300 volts `by an amount corresponding to the maximum of the breathing cycle, or peal; P3 and will maintain these charges temporarily. When t3 is reached, the comparison circuit including tube M6 initiates a sequence of switching operations. Polarized relay i is energized in one direction (after both sets of capacitors have received charges corresponding to the minimum and maximum of the breathing cycle as indicated above) when the breathing cycle signal crosses the base line in a negative going direction. rThe energization of relay coil 1 closes switch la and applies power to relay coils d and :'5 from the plus volt line d4 through the closed upper contact of switch 2u and through conductor 196 to the floating ground line 46. The energization of relay coils 4 and 5' causes them to transfer their contacts from the position illustrated. The transfer of switch :'Sb to its upper contact connects the terminal of capacitor M6 which was previously connected to diode liz to the positive 300 volt line 4th, while the transfer of switch Se to its upper contact connects the terminal of capacitor llo which was previously connected to the minus 300 volt supply to the arm of switch do. This effectively reverses the terminals of condenser lllio so that its charge ditference from that corresponding to plus 300 volts may be measured in the same sense as the charge diiierence of condenser Mft. The closure of relay t causes switch la to move to its left contact and connect condensers lll/l and llo to the input of the integrating amplier. The closure of switch 1lb applies power from the plus 150 volt line lll to relays 2 and 3, the energization circuit for relay 2 being completed through conductor 19o' to the heating-,ground line d6 and the energization circuit of relay Sbeing completed through the upper contact of switch 3b to the same line. The application of power to relay Z brings about its closure and locking through its switch 2a, which closes on its lower contact and completes a circuit through switch lla to the plus 150 volt line 44. The closing of switch 2a on its lower contact opens its upper contact, however, thereby de-energizing relays 4 and 5. The constants ofthe circuits are arranged in such a manner that 7 relays 4 and 5 stay closed for about 1/10 of a second. The closure of relay 2 also applies power to the breathing cycle counter through switch 2b.

When relay 3 is energized, switch 3a is closed, thereby discharging condenser 11S to the floating ground line 45. Similarly the closing of switch 3b on its lower ccntact discharges condenser 12d to the floating ground line. Since relays i and 5 have been de-energized, switches da; 5a and 5b have returned to the positions illustrated,

thereby reconnecting condensers 114 and 116 to the 2.

diode tube 112 and obviating the need for conticnsers 11S and 124, which are used to provide stability and to prevent the diodes Vfrom accumulating unspecified charges when they are disconnected from the measuring capacitors. Relay 3, by the inclusion of condenser 210, is provided with a short time delay so that it does not operate until after relays 4 and 5 have transferred all of their contacts. Relay 3 will reopen subsequent to the de-energization of relay 4 after a short delay. When the breathing cycle again crosses the base line at t4, polarized relay 1 will open and release the locking contact at switch 2o for relay 2, this occurring one-half breathing cycle after the initiation of the relay operating sequence.

When the two measuring capacitors 114 and 116 are transferred to the input of the integrating amplifier, they are discharged to the input potential of this amplifier. This potential is adjusted so as to be negligibly different from the reference floating ground potential. The action ot the integrating amplifier is to provide this reference potential and at the same time to permit the measuring charges to be transferred from the small capacitors 114, 116 and accumulated in the large capacitor constituted by elements 166, which is in the feedback path of the integrating amplier. The transfer of the measuring charges and their accumulation 'oy the large feedback capacitor permits a measurement of the total charge from the start of the run until any time the machine is stopped.

When it is desired to stop the run, the start-stop switch 24 may be placed in its stop and hold position, that is, the position alternate from that illustrated. This disconnects the signal from the input of the instrument and grounds the input circuit, since switch arm 28 is transferred from contact 32 to contact 34, and disables the charge transfer relay circuits. The latter is accomplished by the engagement of switch arm 26 with contact 30, which completes a circuit from the 150 volt line 44 to the coil of relay 2, causing relay 2 to be energized and preventing the energization of relays 4 and 5 through the upper contact of switch 2a (relay 3 is not energized, because resistors 206 and 212 prevent adequate pull-in current). Whatever charge has accumulated in the feedback capacitor will be indicated by meter 164, and the indication will remain for a considerable length of time (up to several days with negligible drift). lf it is desired to reset the integrating amplier for the start of a new run, the reset switch is momentarily closed. This operation discharges the feedback capacitor and returns the indicating meter to zero. A new run may be commenced by returning the start switch 24 to the position illustrated.

Typical components and component values for the circuit of Figure 3 are as follows:

Ref.

6 Capacitors No. Capacitance in microfarads 4S .25 76 1.0 7a .47 30 .02 S8 .001 114 .02 116 .02 118. .02 12d .02 154 .001 156 .05 166 4.0

Resistors No.: Resistance in ohms 30 10K 58 100K 60 300K 64 2.7M 66 1.5M

68 1M '70 270K 72 1.5M

74 200K 200K 470K S4 (downward in order) 33K 22K S6 47K 51K 92 51K 108 1M 110 390K 27K 27K 122 27K 128 300K 130 300K 1.5M 142 1M 144 3M 146 1.5M 14s 3M 15a 1M 152 47K 158 1M 160 la 39th 10K 174 51K 176 51K 178 100K 130 40K 182 560 in it 194 27K 198 27K 204 27K 206 51K 212 27K While a preferred form of the invention has been shown and described, it will be apparent to those skilled in the art that many modifications may be made in this embodiment without departing from the principles of the invention. This embodiment is, therefore, to be taken as illustrative of the invention rather than restrictive and any modifications that lie within the range of equivalents are intended to form a part of the invention as dened in the following claims:

What I claim as my invention is:

1. A system for measuring the sum of the peak values of a continuous incoming signal having successive peaks of opposite polarity, comprising first storage means, means for producing an electric charge in said iirst storage means in direct proportion to the values of said successive peaks of said signal without regard to polarity, second storage means, transfer means for periodically removing the charges in the first storage means and additively accumulating such charges in the second storage means, and indicator means responsive to the total charge stored in said second storage means.

2. A system in accordance with claim l, said first storage means comprising a pair of storage elements, said electric charge producing means comprising means for charging one of said storage elements in direct proportion to signal peaks of one polarity and for icharging the other of said storage elements in direct proportion to signal peaks of the opposite polarity.

3. A system in accordance with claim l, including means for operating said transfer means once during each successive cycle of said signal.

4. A system in accordance with claim l, said transfermeans operating in response to a change from one of i said polarities to the other which polarity change constitutes an end point in each successive cycle of the signal.

5. A system for measuring the sum of successive peak values of a signal which varies positively and negatively with respect to a base level, comprising rst storage means, means for charging said rst storage means in proportion to said peak values, second storage means, comparison means for detecting a change in polarity of said signal with respect to said base level, means operated by said comparison means for discharging said first storage means into said second storage means, and indicating means responsive to the total charge in said second storage means.

6. A `system for measuring the sum of the successive peak values of a continuous incoming signal having successive peaks of opposite polarity which varies positively and negatively in succession with respect to a base level, comprising means for producing a first increment of potential in proportion to the value of each positive peak, means for producing a second increment of potential in proportion to the value of each negative peak, means for cumulatively adding a continuous series of such increments to produce a charge the value of which is equivalent to the sum of such increments, and means for indicating the value of the potential produced in accordance with the sum of said increments.

7. In a system of the type described, a source of continuous incoming signal having successive cycles consisting of peaks of positive and negative polarity with respect to a base level, a pair of condensers, means for charging one of said condensers in proportion to the positive peak of cach cycle, means for charging the other of said condensers in proportion to the negative peak of each cycle, integrating means, and means for transferring the charges from said condensers to said integrating means at the end of each cycle.

8. In the system of claim 7, said charging means including a source of positive potential, a source of negative potential, and a pair of rectiiiers, said source of positive potential lbeing in series with one of said condensers and one of said rectifiers, said source of negative potential being in series with the other of said condensers and 10 the other of said rectiers, said charging means further including means for rendering said rectiiiers conducting in response to negative and positive values of said signal, respectively.

9. ln the system of claim 8, said rectiiiers comprising electron tubes each having a cathode and an anode, the anode of one of said tubes being connected vto the cathode of the other tube, the junction of the last-mentioned cathode and anode being connected to said signal source, and the remaining anode and cathode being connected to said condensers, respectively.

10. A respiration totalizer or the like for determining `the total without regard to sign of the successive peak values of a signal representative of air respired or the like, comprising a variable cut-off frequency means responsive to said signal, a cyclic storage means coupled to the output of said variable cut-off frequency means for storing successive peak values of said signal, integrating means, switch means for rendering said integrating means responsive to said storage means to integrate the signal stored in said storage means without regard to sign, and indicator means responsive to the output of' said integrating means.

ll. A totalizer or the like in accordance with claim 10, further comprising comparison means responsive to the output of said cut-off frequency means `and to a reference signal level for operating said switch means periodically.

12. A totalizer or the like in accordance with claim ll, further comprising cycle counter means responsive to said switch means for adding the number of cycles of said signal applied to said cyclic storage means.

13. A totalizer or the like in accordance with claim 10, said variable cut-oif frequency means comprising an amplifier with a variable gain feedback circuit, said integrating means comprising an amplifier having a feedback loop containing a storage device.

14. A device of the type described for measuring the sum of the peak values of a signal without regard to polarity, comprising a rst condenser, means for charging said first condenser in proportion to peaks of one polarity, a second condenser, means for charging said second condenser in proportion to peaks of the opposite polarity, a third condenser, charge transfer switch means for transferring the charge from said first and second condensers to said third condenser additively, start-stop switch means for rendering said charging means responsive to said signal and alternately nonresponsive to said signal while at the same time disabling said charge transfer switch means, and reset switch means for discharging said third condenser while at the same time disabling said charge transfer switch means.

15. A device in accordance with claim 14, said charge transfer switch means comprising relay means for connecting said iirst and second condensers to said charging means and said third condenser.

16. A device in accordance with claim 15, further in-v cluding indicator means responsive to the charge stored in said third condenser.

17. A system for measuring the sum of the peak values of a signal comprising iirst storage means: including a pair of storage elements, electric charge producing means for charging one of said storage elements in respon-se to signal peaks of one polarity and for charging the other of said storage elements in response to signal peaks of the opposite polarity, second storage means, means for transferring periodically the charge from said rst storage means to said second storage means, said transferring means including means for transferring the charges in said storage elements to said second storage means additively, and indicator means responsive to the total charge stored in said second storage means, whereby said indicator will indicate the sum of said peak values without regard to polarity.

18. In a system of the type described, a source of signal l l 1 2 having values of positive and negative polarity with re- References Cited in the ie of this patent spect to a base level, a pair of condensers, means for UNITED STATES PATENTS charging one of said condensers 1n accordance with said positive values, means for charging the other of said con- 2607528 Mcm/ buter et al Aug' 19 1952 densers in accordance with said negative values, integrati3 2789761 Maru et al' API'- 23 1957 ing means, means for transferring periodically the charge OTHER REFERENCES from said condensers to said integrating means, said transferring means comprising means for comparing the instantaneous value of said signal with a Value representing said base level, and means responsive to said comparison means for discharging said condensers.

Radar Electronics Fundamentals, Navships 900, 016, published `by Bureau of Ships, Navy Dept., Washington, l0 D. C., June 1944. 

